[Che]

I just noticed how the residue was on the inside of the tailpipe is black as. I don't remember it being this dark before - it's usually a charcoal colour if I remember rightly.

I'm not using oil, and I never see smoke out the tailpipe, so i'm just wondering if the colour transition is just the result of running straight LPG for the last 4 months, or maybe something else...


What colour should a healthy exhaust be?

[BlueSuzy]

pink

[want33s]

There is plenty of room to be funny here but.....

If you run unleaded... Sooty black....

The only way to have a nice grey pipe now is to run Avgas which is highly illegal in a car, used to be a good trick for selling shitters, they'd go like stink and with 4-5 times the lead old (pre 88) petrol they'd have a nice clean pipe..

[whincup]

he uses lpg, not unleaded at all. and i misread the "i dont use oil" part, thought you meant you have no oil in there

[MacDaddy]

Yep black is normal for LPG and Unleaded, while your engine doesnt use any noticeable amounts of oil, a motor will usually allow oil to seep past the rings in small amounts, more if its older, this is normal, and means the oil is doing its job...

When we still had the leaded fuel of Standard and Super, the exhaust would be more a grey, and if the car engine was modified, and tuned well, it burnt fuel better, and it would be a light grey, meaning good combustion...

[PJ.zook]

Mate it doesnt really matter what colour the exhaust is as long as its not white. When your exhaust soot turns white, youre up the proverbial creek with no paddle, a fucked engine and a bad tank of fuel